510 
INDEX. 
Magnetism ( terrestrial ), on the variable intensity of, 199. 
influence of the aurora borealis on, 199. 
Mars, on the extensive atmosphere of, 417. 
Matter, every species of, more or less susceptible of transient magnetic energy, 86. 
Moon, on the theory of the, 231. 
N. 
Needle {magnetic), deflected by a rectangle of bismuth only, 107. 
O. 
Observations {meteorological) made at the apartments of the Royal Society in the years 1827, 
1828, 1829, and 1830, on the, 223. 
P. 
Palmer (Henry R. Civil Engineer). Description of a graphical registrer of tides and 
winds, 209. 
Philip (A. P. W. M.D.). On the sources and nature of the powers on which the circu- 
lation of the blood depends, 489. 
Pipes {horizontal and bent), general remarks on the expenditure of, 439. 
Planet {a homogeneous, in a fuid state), on the figure of, 109. 
Planets, on the theory of the motion of, continued from Phil. Trans., Part II. 1830, 
p. 357, 25. 
Platinum , cause of the singular change which occurs in its texture, when heated in the 
black-lead registers, explained, 456. 
Poisons {metallic), electro-chemical method to detect minute quantities of, 147. 
Poncelet and Lesbros (MM.). Results of their experiments on the expenditure of water 
through large rectangular orifices, 441. 
Q. 
Qiiantities, negative and imaginary, on the nature of, 91. 
R. 
Register-pyrometer, further experiments with a new one for measuring the expansion of 
- solids, 443. 
Registrei • {graphical) of tides and winds, 209. 
Rennie (George, Esq.). On the friction and resistance of fluids, 423. 
Robertson (Captain William, II. N.). Observations of the second comet of 1 822, made 
at Rio de Janeiro, 1. 
